Facebook is back with another mea culpa. This time, the company admits that it mishandled sensitive passwords for hundreds of millions of its users, primarily those who use its Facebook Lite product. The disclosure casts doubt and worries on the company's abilities to secures its users' information as it focuses more on privacy.

On Thursday, Facebook (FB) said it didn't properly mask the passwords of hundreds of millions of its users and stored them as plain text in an internal database that could be accessed by its staff and tech contractors.

The company said it discovered the exposed passwords during a security review in January this year and launched an internal investigation. Facebook did disclosed how long it had been storing passwords in this way.